[R] help on ROC analysis

From: zhijie zhang <epistat_at_gmail.com>
Date: Mon, 31 Dec 2007 23:27:45 +0800


Dear all,
  Some functions like 'ROC(Epi)' can be used to perform ROC analyssi, but it needs us to specify the fitting model in the argument. Now i have got the predicted p-values (0,1) for the 0/1 response variable using some other approach, see the following example dataset:

id mark predict.pvalue

1 1 0.927

2 0 0.928

3 1 0.928

..................

*mark* is the true classes, *predict.pvalue* is the predicted p-values, which was used to determine the predicted classes. So i need to specify some cut points for *predict.pvalue*, and then compare it with *mark*class, generate the 2*2 tables, and then calculate some sensitivity, specifity....statistcs, and ROC curve.
 I have searched some functions, such as roc(analogue),'ROC(Epi),etc. They may need to specify the fitting model in the codes or group varibles, and may be not appropriate for my condition. I think that it should have been performed in some package for ROC analysis.   Anybody can tell me which function is for this case?   Thanks very much.

-- 
With Kind Regards,

oooO:::::::::
(..):::::::::

:\.(:::Oooo::
::\_)::(..):: :::::::)./::: ::::::(_/:::: ::::::::::::: [***********************************************************************] Zhi Jie,Zhang ,PHD Tel:+86-21-54237149 Dept. of Epidemiology,School of Public Health,Fudan University Address:No. 138 Yi Xue Yuan Road,Shanghai,China Postcode:200032 Email:epistat_at_gmail.com Website: www.statABC.com [***********************************************************************] oooO::::::::: (..):::::::::
:\.(:::Oooo::
::\_)::(..):: :::::::)./::: ::::::(_/:::: ::::::::::::: [[alternative HTML version deleted]] ______________________________________________ R-help_at_r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Received on Mon 31 Dec 2007 - 15:34:16 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Mon 31 Dec 2007 - 16:30:04 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.

list of date sections of archive